I once saw a large beautiful birdhouse covered in small seashells ... an acquaintance's husband made it for decorative purposes and it sat on a shelf inside their home.

I think a birdhouse covered in small river pebbles would be really pretty ... I might have to try it! I doubt if birds would use it here in our climate because the pebbles would probably really heat up when we have 90º+ during the summer and the poor baby birds would fry. It sure would make a decorative garden accent though so I'm putting it on my list of things to do!

This little wooden birdhouse has been an experiment from 2 years ago. Whether rocks, beads, findings or whatever objects;....I'm believing that if the box is covered in concrete and the objects glued on with contsruction adhesive are wiped off in the early stages before curing; that rocks in small sizes will work well.